Tandems of a telecommunication network are a type of switch (also known as a Class 4 telephone switch) that are typically utilized to connect local exchange carriers that handle local communications to long distance carriers that handle long distance communications. To route long distance communications, tandems are typically dependent or dedicated to a particular region because such tandems are connecting directly to a plurality of local exchange carriers to route any long distance calls originating from or terminating at those local exchange carriers to the long distance carriers. As such, tandems provide transmission support for a particular sector or area of the telecommunications network. In other words, all long distance telephone calls or communications originating from or terminating in a particular region are routed through the tandem associated with that region. For example, a long distance call originating or terminating in Denver, Colo. is typically routed through a tandem associated with Denver or the Denver area. The dedication of a tandem to a region is typically accomplished by assigning an identification number or code, such as an area code, to a specific tandem in the telecommunications network. Any long distance communications with a particular area code associated with the communication will be routed through the tandem that is assigned to handle that particular area code. Similarly, any long distance communications originating from a particular area will be processed by the tandem associated with that area.
The operation of a regionally dependent tandem is provided herein with reference to the network depicted in FIG. 1. In this example, the tandem 108 of region A (104) is configured to process long distance communications originating from or terminating with the communicators 116 of region A. Similarly, the tandem 118 of region B (106) is configured to process long distance communications originating from or terminating in region B. To transmit a communication to the proper tandem switch, the interexchange carrier (IXC) 102 may be configured to determine the originating region and/or the terminating region of a communication transmitted on the telecommunication network. In one example, the communication may be associated with an identification code or other identifying mark that contains destination information for the communication. One such example of an identification mark is an area code and local number. This information may also be associated with a particular tandem switch of the network such that all communications that contain the identification number are routed to that particular tandem. For example, region A (104) may be assigned an identification number for all communications with the destination code of 303-777-xxxx, where “x” is any number. Similarly, region B (106) may be assigned the identification number for all communications with the destination code of 720-555-xxxx, where “x” is any number. In this example, any long distance communication that is directed toward a communication device assigned the 303-777 number is routed through the tandem 108 associated with region A (104) by the IXC 102. Similarly, any long distance communication that is directed to a communication device assigned the 720-555 number is routed through the tandem 118 associated with region B (106) by the IXC 102. In this manner, tandem switches associated with a particular region of the network are configured such that only those communications that share the identification number of the tandem are routed through that particular tandem switch.
Due to this region-specific nature of tandems, a telecommunication network may lack certain flexibility in routing communications through the network to account for complexities and vagaries within the communication network. For example, a disruption to the operation of a tandem may cause a disruption of all communications from and into an entire region supported by the network. In addition, many telecommunication providers utilize a separate internet protocol (IP) network for IP-based communications such that tandems (which are typically utilized in telephonic networks only) are typically unable to handle IP-type communications. Therefore, use of regionally specific tandems limits the effectiveness and flexibility of a telecommunications network.
Hence, among other things, there exists a need for advanced tandem devices and methods in telecommunications networks that provide flexibility in communication routing through the network and to generally de-regionalize the tandem switches.